OBJECTIVE: The goal of this project is to improve the restoration of function following the severance and repair of peripheral nerves in man. We have developed a tubulization method of fascicular (perineurial) repair with a new hypoantigenic (telopeptide-poor) collagen membrane. Improved nerve regeneration has been demonstrated in our end-to-end monofascicular experimental (rat) model, however its ultimate effect on clinical function has not been determined. This requires further evaluation of fascicular tubulization in more clinically applicable animal (cat and primate) multifascicular nerve models. We plan to: 1) study end-to-end nerve repair methods to determine the best method to repair simple transections with minimal nerve loss. 2) study graft nerve repair methods to determine the best method to repair transections with extensive nerve loss (gaps). 3) study varying nerve gaps to determine under what circumstances a graft repair or an end-to-end nerve repair should be used to provide the best recovery. These nerve repairs will be evaluated by invasive methods as well as noninvasive methods that are applicable to clinical studies, thus facilitating correlation of animal results to the clinical level of recovery.